Research On Operation Technology Of Underwater Vehicle-Dual-Manipulator System

With the exploitation and consumption of terrestrial resources,mankind has gradually focused on the marine field,which contains abundant minerals,fuels,and biological resources became the global attention in recent years.Under this trend,the development of marine engineering equipment has been greatly promoted such as underwater vehicle-manipulator system(UVMS),as one of the main ocean engineering equipment,plays an indelible role.However,UVMS is a non-linear,strong-coupling and degree-of-freedom redundant system.The control for UVMS is actually the system dynamics problem and the multi-degree of freedom planning problem,which are the core of solving the control problem of UVMS.Therefore,this paper starts with dynamics modeling of underwater vehicle-dual manipulator system,to analyze the coupling effect between vehicle and manipulator,and research on the coordination planning of underwater vehicle-dual-manipulator system.Firstly,DH method has been adopted to establish the forward kinematics equation of the manipulator according to the actual design size of the manipulator in the underwater vehicle-manipulator system developed by this project,and the inverse kinematics problem is solved by geometric method.Then the differential motion relation of vehicle and manipulator is established to pave the way for task-priority planning of underwater vehicle-dual-manipulator system.Based on the forward kinematics of manipulator,MATLAB is used to analyze the working space of dual-arm manipulator.In practical project,for the characteristics of dual-arm cooperative grasping task,the dual-arm cooperative workspace is extracted based on the dual-arm workspace,and the three-dimensional cloud image of cooperative workspace is generated to verify the ability of dual-arm cooperative.Secondly,dynamics model of manipulator system has been established with actual design parameters of the manipulator by the Lagrange method,which consists of inertial term,Coriolis force and centriolar force and gravity term,so as to obtain the manipulator control model,and underwater manipulator hydrodynamic has been analyzed.Based on Newton-Euler formula,the coupling force and torque of the manipulator effected on the underwater vehicle were derived.Therefore,the underwater vehicle-dual-manipulator system dynamic model is established by combining the AUV dynamic model and underwater manipulator model.Thirdly,the motion of the motor is planned by the three polynomial and five polynomial interpolation method in the joint space,which is used for simulation for manipulator to compare the advantages and disadvantages of the two planning methods.Then,according to the redundant characteristics of the underwater vehicle-dual-manipulator system model,the task priority planning method is adopted to solve the multi-DOF allocation problem.Based on engineering practice,simulation experiments has been carried out on underwater vehicle-dual-manipulator system grasping under three different conditions,and the results proved that the effectiveness of this method in the application of underwater vehicle-dual-manipulator system.Finally,aiming at the specific grasping action in practical application,dynamics simulation is carried out for the model in this paper with qualitative and quantitative analysis conducted for the coupling effect between vehicle and manipulator,and combined with the manipulator planning method,the perturbation influence of the manipulator on the boat body under different methods and different motion speeds has been tested respectively,laying a foundation for the practical application of manipulator.Finally,based on the previous theoretical research,it applies three polynomial interpolation method on the practical system and PID control algorithm has been adopted to carry out motion test and planning algorithm verification for the joint motor.Next,the whole arm was tested,and the dual-arm manipulator cooperative grasping experiment was carried out further,which verified grasping ability of the underwater dual-arm manipulator cooperative.